The present invention is drawn to a device for compacting granular molding material and, more particularly, a device for compacting granular molding material by a pulse of compressed gas and/or mechanical squeeze.
There exists in the prior art various processes and devices for compacting granular molding materials which are particularly useful in producing sand molds for metal casting. The known devices include devices capable of providing a one-stage compaction by either a pulse of compressed gas or a mechanical squeeze and multi-stage compaction which includes a combination of gaseous pulses and mechanical squeeze. A particular useful device known in the prior art employs precompaction by a pressure surge of gaseous material followed by final compaction by mechanical squeeze.
Naturally, it would be highly desirable to provide a device which is capable of carrying out known compaction processes in a selective manner depending on the pattern requirements of the resulting sand mold.
Accordingly, it is the principal object of the present invention to provide a device for compacting granular molding materials in accordance with known compaction processes which may be operated selectively depending on the pattern requirements.